POS0752 DISEASE FEATURES AT DIAGNOSIS AND CHANGES IN DISEASE COURSE SEVERITY AMONG PATIENTS WITH CHILDHOOD-ONSET COMPARED TO ADULT-ONSET SYSTEMIC LUPUS ERYTHEMATOSUS
Authors: A. Phillips-Beyer, Q. Li, M. E. Stokes, M. Pozzobon Da Silva
Journal: Annals of the Rheumatic Diseases (2022)

Background Systemic lupus erythematosus (SLE) is characterised by a heterogeneous clinical presentation with alternating periods of remission and relapse. Disease severity is determined by the type and level of involvement of different organ systems. SLE can occur in childhood or later in life, and patients may present with differing levels of disease severity according to the age of onset. Changes in disease severity following treatment may also differ depending on age of onset. There are limited data that document these differences. Objectives To compare demographic and clinical characteristics including baseline disease severity and changes in severity over time between patients with childhood-onset and adult-onset SLE in the United States. Methods We identified patients aged 0–64 years and diagnosed with SLE during 2015–2019 using the IBM MarketScan claims databases. SLE severity was determined using a published algorithm, which combines elements of organ involvement and the use of SLE-related medications to assign patients to mild, moderate, and severe disease states. 1 Baseline disease severity was determined using a 90-day period following the initial SLE diagnosis. The index date was the day after this initial 90-day period. Baseline comoribidities were assessed during the 12 months prior to the index date. Disease severity was evaluated at 0 to &lt;6 months, ≥6 to &lt;12 months, and ≥12 to &lt;24 months post-index. Patients were categorised according to the highest severity level identified during each period. Changes in severity vs. baseline were also measured during each evaluation period. For example, worsening severity was defined as a transition from a lower to higher disease severity state (e.g., moderate to severe). Analyses were conducted separately for cohorts with Commercial Health Insurance (CHI) and Medicaid. Within each cohort, patients with childhood-onset (≤17 years) were descriptively compared to those with adult-onset (≥18 years) SLE. Results Most enrolees were female (CHI: 90%, Medicaid: 92%). Mean age at index date was 14.0 vs. 43.4 years for childhood- and adult-onset groups, respectively. Baseline infections were more prevalent among children vs. adults in both CHI (41.4% vs. 30.1%) and Medicaid (45.3% vs. 39.3%) cohorts (Table 1). A higher proportion of children vs. adults had severe disease at baseline in the CHI (38.3% vs. 10.7%) and Medicaid (48.0% vs. 14.2%) cohorts. Overall, the largest decreases in SLE severity compared to baseline were observed during ≥6 to &lt;12 months of follow-up. Children were more likely to experience a decrease in severity than adults. During ≥12 to &lt;24 months, 19.9% of children in the Medicaid cohort had an increase in severity compared to baseline vs. only 12.3% of children in the CHI cohort. Table 1. Profiles of patients with SLE Characteristic % Commercial Health Plan Medicaid 0–17 years 18–64 years 0–17 years 18–64 years (N=290) (N=10,622) (N=298) (N=3,143) Age in years at index date, mean (SD) 14.2 (2.7) 44.6 (12.0) 13.7 (3.1) 39.2 (11.9) Median (range) 15.0 (1−17) 48.0 (18−64) 15.0 (2−17) 39.0 (18−64) Female 86.7% 90.1% 83.9% 93.1% Baseline treatment Corticosteroids 77.6% 69.3% 84.6% 69.7% Immunomodulators 42.4% 23.2% 55.0% 19.4% Antimalarials 71.7% 60.5% 80.2% 49.1% SLE severity change from baseline 0–&lt;6 months follow-up Increase 10.9% 20% 7.5% 21.7% Decrease 20.9% 17.2% 25.9% 18.8% ≥6–&lt;12 months follow-up Increase 11.6% 20.4% 9.2% 22.8% Decrease 36.7% 19.9% 39.5% 22.7% ≥12–&lt;24 months follow-up Increase 12.3% 30.1% 19.9% 33.2% Decrease 33.3% 15.6% 38.0% 17.8% SD, standard deviation. Conclusion Children with SLE present with greater severity of symptoms compared to adults and are more likely to experience an improvement following the initial treatment period. References [1]Garris C, et al. Healthcare utilization and cost of systemic lupus erythematosus in a US managed care health plan. J Med Econ. 2013;16(5):667-677 Disclosure of Interests Andrea Phillips-Beyer Consultant of: Idorsia Pharmaceuticals, Qian Li Consultant of: Idorsia Pharmaceuticals, Michael E. Stokes Consultant of: Idorsia Pharmaceuticals, Marilia Pozzobon da Silva Employee of: Idorsia Pharmaceuticals